The subject matter disclosed herein relates to fuses, and particularly to a switch box arrangement that includes fuses.
Traditional alternating current (AC) switch boxes often include an array of switches and fuses that correspond to each phase of a multi-phase electrical distribution system. The switches are arranged to disconnect the line side of the fuses from the incoming voltage of a respective phase.
The switch boxes often include an external lever that is mechanically linked to the switches such that actuating the external lever opens and closes the switches. In operation, a technician operates the external lever to open the switches, thereby isolating the fuses prior to opening an access panel or door that exposes the fuse and switches for maintenance or troubleshooting.
The electrical connection between the fuses and components that may be connected to the fuses may result in a “back feeding” state where a voltage may be present at the fuse even if the fuse is partially isolated from the system with a switch. Thus, prior to accessing the fuse during installation, maintenance, or troubleshooting, a technician should determine whether a voltage is present at the fuse. If a voltage is present at the fuse, the technician should not access the fuse until the source of the voltage is isolated from the fuse.
Previous examples of switch boxes included labels that would remind a technician to test the fuses with a volt meter to ensure that there is no voltage present at the fuse prior to accessing the fuse.